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mysqld_safe is the recommended way to start a mysqld
server on Unix and NetWare. mysqld_safe adds some safety
features such as restarting the server when an error occurs and logging runtime
information to an error log file. Descriptions of error logging and
NetWare-specific behaviors are given later in this section.

mysqld_safe tries to start an executable named mysqld. To
override the default behavior and specify explicitly the name of the server you
want to run, specify a --mysqld or --mysqld-version option to
mysqld_safe. You can also use --ledir to indicate the
directory where mysqld_safe should look for the server.

Many of the options to mysqld_safe are the same as the
options to mysqld.

Options unknown to mysqld_safe are passed to mysqld if they
are specified on the command line, but ignored if they are specified in the
[mysqld_safe] group of an option file.

mysqld_safe reads all options from the [mysqld],
[mysqld_safe] and [mariadb_safe] sections in option files. For example, if
you specify a [mysqld] section like this, mysqld_safe will
find and use the --log-error option:

[mysqld]
log-error=error.log

For backward compatibility, mysqld_safe also reads
[safe_mysqld] sections, although you should rename such sections to
[mysqld_safe] in MariaDB installations.

mysqld_safe Options

mysqld_safe supports the following options:

--help

Display a help message and exit.

--autoclose

(NetWare only) On NetWare, mysqld_safe provides a
screen presence. When you unload (shut down) the
mysqld_safe NLM, the screen does not by default go away.
Instead, it prompts for user input:

*<NLM has terminated; Press any key to close the screen>*

If you want NetWare to close the screen automatically instead, use the
--autoclose option to mysqld_safe.

--basedir=path

The path to the MariaDB installation directory.

--core-file-size=size

The size of the core file that mysqld should be able to create. The
option value is passed to ulimit -c.

--datadir=path

The path to the data directory.

--defaults-extra-file=path

The name of an option file to be read in addition to the usual option
files. This must be the first option on the command line if it is used. If
the file does not exist or is otherwise inaccessible, the server will exit
with an error.

--defaults-file=file_name

The name of an option file to be read instead of the usual option files.
This must be the first option on the command line if it is used.

--ledir=path

If mysqld_safe cannot find the server, use this
option to indicate the path name to the directory where the server is
located.

--log-error=file_name

Write the error log to the given file.

--mysqld=prog_name

The name of the server program (in the ledir directory) that you want to
start. This option is needed if you use the MariaDB binary distribution but
have the data directory outside of the binary distribution. If
mysqld_safe cannot find the server, use the --ledir
option to indicate the path name to the directory where the server is
located.

--mysqld-version=suffix

This option is similar to the --mysqld option, but
you specify only the suffix for the server program name. The basename is
assumed to be mysqld. For example, if you use
--mysqld-version=debug, mysqld_safe
starts the mysqld-debug program in the ledir directory. If the argument to
--mysqld-version is empty, mysqld_safe
uses mysqld in the ledir directory.

--nice=priority

Use the nice program to set the server´s scheduling priority to the
given value.

--no-defaults

Do not read any option files. This must be the first option on the
command line if it is used.

--open-files-limit=count

The number of files that mysqld should be able to open. The option value
is passed to ulimit -n. Note that you need to start
mysqld_safe as root for this to work properly!

--pid-file=file_name

The path name of the process ID file.

--port=port_num

The port number that the server should use when listening for TCP/IP
connections. The port number must be 1024 or higher unless the server is
started by the root system user.

--skip-kill-mysqld

Do not try to kill stray mysqld processes at startup. This option works
only on Linux.

--socket=path

The Unix socket file that the server should use when listening for local
connections.

--syslog, --skip-syslog

--syslog causes error messages to be sent to syslog
on systems that support the logger program. --skip-syslog suppresses the
use of syslog; messages are written to an error log file. These options were
added in MySQL 5.1.20.

--syslog-tag=tag

For logging to syslog, messages from mysqld_safe and
mysqld are written with a tag of mysqld_safe and mysqld,
respectively. To specify a suffix for the tag, use
--syslog-tag=tag, which modifies the tags to be
mysqld_safe-tag and mysqld-tag. This option was added in
MySQL 5.1.21.

--timezone=timezone

Set the TZ time zone environment variable to the given option value.
Consult your operating system documentation for legal time zone
specification formats.

--user={user_name|user_id}

Run the mysqld server as the user having the name user_name or the
numeric user ID user_id. (“User” in this context refers to a system login
account, not a MySQL user listed in the grant tables.)

If you execute mysqld_safe with the
--defaults-file or --defaults-extra-file
option to name an option file, the option must be the first one given on the
command line or the option file will not be used. For example, this command
will not use the named option file:

mysql> mysqld_safe --port=port_num --defaults-file=file_name

Instead, use the following command:

mysql> mysqld_safe --defaults-file=file_name --port=port_num

The mysqld_safe script is written so that it normally can
start a server that was installed from either a source or a binary distribution
of MariaDB, even though these types of distributions typically install the server
in slightly different locations.
mysqld_safe expects one of the following conditions to be
true:

The server and databases can be found relative to the working directory
(the directory from which mysqld_safe is invoked). For
binary distributions, mysqld_safe looks under its working
directory for bin and data directories. For source distributions, it looks
for libexec and var directories. This condition should be met if you execute
mysqld_safe from your MariaDB installation directory (for
example, /usr/local/mysql for a binary distribution).

If the server and databases cannot be found relative to the working
directory, mysqld_safe attempts to locate them by absolute
path names. Typical locations are /usr/local/libexec and
/usr/local/var. The actual locations are determined from
the values configured into the distribution at the time it was built. They
should be correct if MariaDB is installed in the location specified at
configuration time.

Because mysqld_safe tries to find the server and databases
relative to its own working directory, you can install a binary distribution of
MariaDB anywhere, as long as you run mysqld_safe from the
MariaDB installation directory:

shell> cd mysql_installation_directory
shell> bin/mysqld_safe &

If mysqld_safe fails, even when invoked from the MariaDB
installation directory, you can specify the --ledir and
--datadir options to indicate the directories in which the
server and databases are located on your system.

When you use mysqld_safe to start mysqld,
mysqld_safe arranges for error (and notice) messages from
itself and from mysqld to go to the same destination.

As of MySQL 5.1.20, there are several mysqld_safe options
for controlling the destination of these messages:

--syslog: Write error messages to syslog on systems that
support the logger program.

--skip-syslog: Do not write error messages to syslog.
Messages are written to the default error log file (host_name.err in the data
directory), or to a named file if the --log-error option
is given.

--log-error=file_name: Write error messages to the named
error file.

If none of these options is given, the default is --skip-syslog.

Note: In MySQL 5.1.20 only, the default was --syslog. This differs from
logging behavior for other versions of MariaDB and MySQL, for which the default is to write
messages to the default error log file.

If --syslog and --log-error are both
given, a warning is issued and --log-error takes precedence.

When mysqld_safe writes a message, notices go to the logging
destination (syslog or the error log file) and stdout. Errors go to the logging
destination and stderr.

Before MySQL 5.1.20, error logging was controlled only with the --log-error
option. If it is given, messages go to the named error file. Otherwise,
messages go to the default error file.

Normally, you should not edit the mysqld_safe script.
Instead, configure mysqld_safe by using command-line options
or options in the [mysqld_safe] section of a my.cnf option
file. In rare cases, it might be necessary to edit
mysqld_safe to get it to start the server properly.
However, if you do this, your modified version of
mysqld_safe might be overwritten if you upgrade MariaDB in the
future, so you should make a copy of your edited version that you can
reinstall.

On NetWare, mysqld_safe is a NetWare Loadable Module (NLM)
that is ported from the original Unix shell script. It starts the server as
follows:

Runs a number of system and option checks.

Runs a check on MyISAM tables.

Provides a screen presence for the MariaDB server.

Starts mysqld, monitors it, and restarts it if it terminates in error.

Sends error messages from mysqld to the host_name.err file in the data directory.

Sends mysqld_safe screen output to the host_name.safe file
in the data directory.

Note: In MySQL 5.1.20 (only), the default error logging behavior with
mysqld_safe is to write errors to syslog on systems that
support the logger program. This differs from the default behavior of
writing an error log file for other versions.

In 5.1.20, logging to syslog may fail to operate correctly in some cases; if so, use
--skip-syslog to use the default log file or
--log-error=//file_name// to specify a log file name explicitly.